Typically, eco-friendly vehicles use an electric motor as a driving source of a vehicle, and substantial development efforts have been invested in developing a technology for storing electric energy such as a battery, or the like, which provides a power source for the eco-friendly vehicle. Further, substantial effort has been invested in research and development of internal and external apparatuses of the vehicle for charging the battery and charging equipment, and developing a charge infrastructure.
Generally, eco-friendly vehicle such as an electric vehicle or a hybrid vehicle are mounted with an electric motor, which is the driving source of the vehicle, a motor controller unit (MCU) that includes an inverter for driving and operating the electric motor, a battery for supplying driving power of the electric motor, and an in-vehicle charger for charging the battery, and a charging port that connects the vehicle and an external charger to each other. Additionally, the vehicle includes a battery management system (BMS) that monitors a state of the battery. The battery management system collects state information of the battery such as a voltage, a current, a temperature, a state of charge (SOC), etc., of a battery pack, and provides the collected state information of the battery to internal and external controllers of the vehicle to be used for a vehicle control, a charge control, or the like.
Furthermore, the battery of the eco-friendly vehicle may be slowly charged by connecting alternating current (AC) power to the vehicle, or may be rapidly charged by connecting direct current (DC) power to the vehicle. When a slow charger supplies the AC power to the vehicle, an on-board charger (OBC) within the vehicle converts the AC power into the DC power and charges the battery with the DC power. Conversely, when a rapid charger, which is a charger configured to convert the AC power into the DC power and supplies the DC power to the vehicle, and directly connects the battery in the vehicle to provide a high current, the rapid charger may complete the charge of the battery in a minimal duration of time.
To perform the charge of the battery described above, a connector of the charger (e.g. the slow charger or the rapid charger) may be connected to the charging port of the vehicle, and charged power of the charger may be supplied to the vehicle by the connector. The connector includes a plurality of terminals such as a communication terminal for a communication connection with the vehicle, a communication power supply terminal, a ground connection terminal, in addition to a power supply terminal configured to supply the charged power.
Additionally, a power line of the vehicle includes a power relay assembly (PRA) for a selective power supply and interruption. The power relay assembly includes a plurality of high voltage relays which are configured to interrupt a high voltage of a high voltage battery, and are connected to each other when engaging an ignition, and are disconnected from each other when disengaging an ignition. However, a fusion occurs that may cause the contact points of the high voltage relay to frequently be immobilized. Accordingly, there is a need for a method of detecting the fusion and performing the detection of the fusion during engagement or disengagement of the ignition.